Many different silicones are known to provide abrasion, scratch, and mar resistance to coatings. In most cases they tend to bloom, that is, over a period of time they tend to migrate to the surfaces of the coatings of which they are constituents, where they can be removed by wiping, washing, or the like. Not only does this effectively remove the beneficial properties the silicones provide to the coatings, but residual bloom often substantially interferes with paintability and hence with recoating or repair coating operations.
Another important property of coatings is gloss. For many coatings, especially automotive coatings, high gloss is a very desirable property. Gloss is a function of refractive index such that an increase in the refractive index of the coating results in higher gloss.